The present disclosure relates to containers in general, and more particularly to containers that are closed by a metal end seamed onto the container body.
For many years the standard technique for attaching a metal end to a metal container body has been the double-seaming method, in which a curled outer edge of the metal end and a flange formed on the container body are rolled up together to form a hermetic seam. The double-seaming technique essentially entails mechanically locking together the metal end and the container body flange. Double-seaming works well for metal container bodies because the metal is ductile and permanently deformable without compromising the integrity of the seam, but encounters difficulties when the container body is plastic or composite because of the relative lack of ductility and lack of permanent deformability of such materials.